Physical quality changes of pre-cooked shrimps during frozen storage

The physical quality (texture and color), moisture content, water holding capacity, low-field nuclear magnetic resonance (NMR) transverse relaxation T-2 data and the correlation among these indexes in pre-cooked (boiled for 5 min) Chinese shrimp Fenneropenaeus chinensis during frozen storage were investigated. The moisture content, water holding capacity, and springiness decreased with the storage time increasing, while L*, a*, b* and hardness increased. The correlation analysis result showed that the hardness, L*, a* and b* value were direct proportion to P-2b, the springiness was direct proportion to P-21 and P-22, respectively, moisture content was inverse proportion to hardness, while direct proportion to springiness. The changes of water mobility and distribution of pre-cooked Chinese shrimp Fenneropenaeus chinensis resulted in the changes of apparent quality(color and texture).